Performance difference using texture slabs?

do you know if it makes a big performance difference by placing all your textures on a single 2048x2048 slab, and sharing that texture slab across all the objects as oppose to keeping all the textures as separate files.

Traditional game design would say yes, but I’m getting the feeling that Unity doesn’t work that way. Because when I compared the frame rate to a hundred objects with the shared texture slab, to the frame rate with the same objects but the textures where in their separate files. I saw no noticeable difference. And in neither scenario was I getting my objects to batch together.

Is their any advice on the real time practices for unity? I’m traditionally a pre-rendered animation kind of graphics artist so the real time stuff is pretty new. And unity doesn’t seem to follow the same rules as traditional real time applications.

This was the best answer i received on google+:

It sort of depends sometimes though; in that it takes more memory then you need to use a lot. Example:

scene 1 was objects A and B
scene 2 has objects C and D
A, B, C and D all share the same texture

Now in this case half of the texture space (in memory) is wasted in each scene because you never see all the objects at the same time; so it would be better to just use 2 textures. But most of the time on mobile, draw calls are a bigger problem then memory for me. And furthermore dynamic batching has other variables.

In theory it’s better to have single texture - Unity can batch objects (as long as they are using same material). In practice it might not matter if your game is CPU, vertex count or fillrate limited (as opposed to “draw call” limited).

I believe batching is a Unity Pro feature too.